Easy-detachable grinding device for cement walk-behind trowel machine

ABSTRACT

An easy-detachable grinding device for a cement walk-behind trowel machine comprises a plurality of installing units arranged on a seat which is installed with the central disk and the outer rotary disks. In use, it is only needed to buckle the installing units to the grinding knives of a power source of a cement walk-behind trowel machine so that the central disk and the outer rotary disks are assembled to the cement walk behind trowel machine. The original grinding knives are unnecessary to be detached from the cement walk behind trowel machine. Furthermore the grinding device can be detached easily as it is not used, while the original used grinding knives can be used again. No more vehicle is needed. Outer rotary disks are arranged on the periphery of the central disk so as to have a large grinding area.

FIELD OF THE INVENTION

The present invention is related to cement grinding, and in particularto an easy-detachable grinding device for a cement walk-behind trowelmachine (ride-on trowel machine).

BACKGROUND OF THE INVENTION

In civil engineering, it is often necessary to pave cement on ground.Firstly, wet cement is paved on the ground, and then grinding knives areused to flat the cement. The grinding knives are installed on awalk-behind trowel machine (ride-on trowel machine) which has a grindingknife device. It has a rotatable frame and a plurality of grindingknives installed thereon. The grinding knives have the function offlattening wet cement ground.

In above mentioned prior art, the grinding knives cannot completely flatthe ground because after the cement is solidified, the cement ground isstill uneven. This is not beneficial for the succeeding works and italso presents an unbeautiful outlook. If it is desired to flatten thesolidified cement ground, another tools are necessary. This causesoverall cost to be increased.

SUMMARY OF THE INVENTION

Accordingly, the object of the present invention is to provide aneasy-detachable grinding device for a cement walk-behind trowel machine(ride-on trowel machine), wherein advantages of the present inventionare that installing units are arranged on a seat which is installed withthe central disk and the outer rotary disks. In use, it is only neededto buckle the installing units to the grinding knives of a power sourceof a cement walk-behind trowel machine so that the central disk and theouter rotary disks are assembled to the cement walk behind trowelmachine. The installing work is easy and convenient. The originalgrinding knives are unnecessary to be detached from the cement walkbehind trowel machine. Furthermore the grinding device of the presentinvention can be detached easily as it is not used, while the originalused grinding knives can be used again. No more vehicle is needed. Inthe present invention, the outer rotary disks are arranged on theperiphery of the central disk so as to have a large grinding area. Bythe revolution of the outer rotary disks with respective to the centraldisk and the rotation of the outer rotary disks, the cement surface canbe ground effectively so that the whole cement surface is uniformlyground to present a beautiful outlook. This is beneficial to thesucceeding works.

To achieve above object, the present invention provides aneasy-detachable grinding device for a cement walk-behind trowel machinewhich is installed to a power output shaft of a power source of a cementwalk-behind trowel machine, the grinding device comprising: a rotationframe including a primary body and a plurality of supporting framesconnected to the primary body; a center of the primary body having athrough hole; in assembly, the power output shaft of the power sourcebeing inserted into the through hole so that the power source can drivethe rotation frame to rotate; each supporting frame extending from theprimary body; an outer side of each supporting frame be installed with agrinding knife unit; a seat installed below the rotation frame; an upperperiphery of the seat being formed with a plurality of installing unit;each installing unit being positioned below an outer side of arespective supporting frame; the installing seat serving to be connectedto a grinding knife unit; rotation of the rotation frame will drive theseat to rotate; a central disk located below the seat; a center of thecentral disk having an installing hole; a rotating shaft being installedin the installing hole; the rotating shaft being fixed therein by usinga stepped bearing so that rotation of the rotating shaft does not drivethe central disk to rotate; the rotating shaft extending from theinstalling hole upwards; an upper end of the rotating shaft connected tothe seat; the through hole and the rotating shaft being coaxial; whenthe rotation frame rotates, the seat is driven to rotate so as to drivethe rotating shaft to rotate; and a plurality of outer disks arrangedbelow the seat; a center of each outer disk having an assembly hole; anaxial post being installed in the assembly hole; an upper end of eachaxial post being connected to the seat; a bottom of each outer diskbeing installed with at least one outer grinding sheet; and wherein whenthe power output shaft rotates, the seat is driven to rotate, the poweroutput shaft drives the rotation frame to rotate so that the outer disksrevolve around the central disk; as a result, the outer grinding sheetsrotate around the central disk so as to grind the surface of the cementground; and one side of the installing unit installed with a trench; inassembly state, one side of the grinding knife unit being embedded intothe trench so tha the installing unit being tightly engaged with thegrinding knife unit; on side of the grinding knife unit can be foldedupwards so that the grinding knife unit being extremely steadily fittedto the trench of the installing unit.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a schematic view of the present invention.

FIG. 2 is an exploded schematic view about the elements of the presentinvention.

FIG. 3A is a cross sectional schematic view of the present inventionalong line A-A of FIG. 1 .

FIG. 3B is a cross sectional schematic view along line B-B of FIG. 1 .

FIG. 4A is a cross sectional schematic view along line C-C of FIG. 1 .

FIG. 4B is cross sectional schematic view showing another assembly wayfor the grinding knife unit shown in FIG. 4A.

FIG. 5 is a lower side schematic view showing the assembly of thecentral disk and the outer rotary disks.

FIG. 6 is a schematic view showing that the present invention isassembled to a two head cement walk-behind trowel machine.

FIG. 7 is a schematic view showing that the present invention isassembled to a single head cement walk-behind trowel machine.

DETAILED DESCRIPTION OF THE INVENTION

In order that those skilled in the art can further understand thepresent invention, a description will be provided in the following indetails. However, these descriptions and the appended drawings are onlyused to cause those skilled in the art to understand the objects,features, and characteristics of the present invention, but not to beused to confine the scope and spirit of the present invention defined inthe appended claims.

The easy detachable grinding unit 5 of the present invention isinstalled to the power output shaft 61 of the power source 60 of acement walk-behind trowel machine (ride-on trowel machine) 6 which mayhave two grinding sets (referring to FIG. 6 ) or a single one grindingset (referring to FIG. 7 ). The grinding unit 5 includes the followingelements.

A rotation frame 1 includes a primary body 11 and a plurality ofsupporting frames 12 connected to the primary body 11. A center of theprimary body 11 has a through hole 111. In assembly, the power outputshaft 61 of the power source 60 is inserted into the through hole 111 sothat the power source 60 can drive the rotation frame 1 to rotate. Eachsupporting frame 12 extends outwards from the primary body 11. An outerside of each supporting frame 12 is installed with a grinding knife unit121.

A seat 14 is installed below the rotation frame 1. An upper periphery ofthe seat 14 is formed with a plurality of installing unit 141. Eachinstalling unit 141 is positioned below an outer side of a respectivesupporting frame 12. The installing seat 141 serves to be connected to agrinding knife unit 121. Rotation of the rotation frame 1 will drive theseat 14 to rotate. One side of the installing unit 141 is installed witha trench 142. In assembly state, one side of the grinding knife unit 121is embedded into the trench 142 so tha the installing unit 141 istightly engaged with the grinding knife unit 121, as shown in FIG. 4A.On side of the grinding knife unit 121 can be folded upwards so that thegrinding knife unit 121 is extremely steadily fitted to the trench 142of the installing unit 141.

The seat 14 has a flat sheet form. Preferably, all trenches 142 ofinstalling units 141 are arranged at the same side along a circulatepath (clockwise or counterclockwise) so that all grinding knife units121 can be engaged into the trenches 12 along a clockwise orcounterclockwise path. Preferably, rotation direction of the rotationframe 1 is identical to the direction that the grinding knife units 121engages into the trenches 142 of the installing units 142, so that asthe rotation frame 1 rotates, the grinding knife units 121 resistsagainst inner walls 143 of the trenches 142 for preventing the grindingknife units 121 from dropping out from the trenches 141.

A central disk 2 is below the seat 14. A center of the central disk 2has an installing hole 25. A rotating shaft 21 is installed in theinstalling hole 25. The rotating shaft 21 is fixed therein by using astepped bearing 251 so that rotation of the rotating shaft 21 does notdrive the central disk 2 (referring to FIG. 2 ). The rotating shaft 21extends from the installing hole 25 upwards. An upper end of therotating shaft 21 connected to the seat 14. The through hole 111 and therotating shaft 21 are coaxial. When the rotation frame 1 rotates, theseat 14 is driven to rotate so as to drive the rotating shaft 21 torotate.

A plurality of outer disks 3 are arranged below the seat 14 and aroundthe periphery of the central disk 2. A center of each outer disk 3 hasan assembly hole 35. An axial post 31 is installed in the assembly hole35. An upper end of each axial post 31 is connected to the seat 14. Abottom of each outer disk 3 is installed with at least one outergrinding sheet 32. In this example, the grinding unit 5 includes fourouter disks 3. A bottom of each outer disk 3 is installed with threeouter grinding sheets 32.

In grinding a surface of the cement ground, the grinding unit 5 of thepresent invention may be installed to a two head walk-behind trowelmachine 6 (see FIG. 6 ) or to a one head walk-behind trowel machine 7(see FIG. 7 ). In assembly, the power output shaft 61 of the powersource 60 of the grinding machine 5, 6 is inserted into the through hole111 of the rotation frame 1. When the power source 60 operates, thepower output shaft 61 will drive the grinding unit 5 to grind.Preferably, the power source 60 is a motor or an engine.

When the power output shaft 61 rotates, the power output shaft 61 willdrive the rotation frame 1 to rotate and thus further to drive the seat14 to rotate so that the outer disks 3 revolve around the central disk2. As result, the outer grinding sheets 32 rotate around the centraldisk 2 so as to grind the surface of the cement ground.

With reference to FIGS. 1, 2, 3B and 5 , an outer periphery of thecentral disk 2 is formed with an outer teeth unit 231 so that the wholestructure is as a central belt wheel 23. Each outer disk 3 includes diskbody 37 and an outer belt wheel 33 fixed to the disk body 37. Theassembly hole 35 is formed in a center of the outer belt wheel 33. Alower end of the axial post 31 is fixed to the assembly hole 35 of theouter disk 3 by using a stepped bearing 351 to buckle the axial post 31therein. The outer grinding sheets 32 are installed at a bottom of thedisk body 37. The grinding unit 5 of the present invention furtherincludes a transfer unit 4 which encircles the central belt wheel 23 andthe outer belt wheels 33. When the rotation frame 1 rotates to drive theseat 14 to rotate, the outer grinding sheets 32 of the outer disks 3 aredriven to revolve around the central disk 2 to grind and moreover thetransfer unit 4 further drives the outer belt wheels 33 to rotate andthe outer disks 3 rotates around a center of itself. As a result eachouter grinding sheet 32 revolves around the axial post 31 of the outerdisk 3 so as to further grind. Then, the central belt wheel 23 mayrotate or not rotate with the transfer unit 4. The transfer unit 4 maybe belt or chain 23.

Preferably, the outer disks 3 are arranged to be spaced with an equalspace.

In the preferred embodiment of the present invention, a lower side ofthe central belt wheel 23 is arranged with a slide proof pad 22(referring to FIG. 3B). A plurality of elastic bodies 24 are arrangedbetween the central belt wheel 23 and the slide proof pad 22. By theelasticity of the elastic bodies 24, the slide proof pad 24 may move upand down for generating slide proof effect to the rotation of the outerdisk 3 and to reduce the rotation speed of the central disk 2 by theslide proof between the slide proof pad 22 and the cement surface.Therefore, since the diameter of the central belt wheel 23 is largerthan that of the outer belt wheel 33, the speed reduction of the centralbelt wheel 23 will cause the transfer unit 4 properly adjusts therotation speed of the outer belt wheel 33.

An outer periphery of the seat 14 is formed with a plurality ofconnecting holes 70 each of which receives an upper end of an axial post31 of a respective outer disk 3. The connecting holes 70 are classifiedas at least one retaining hole 71 and at least one active hole 72. Theaxial post 31 installed into the retaining hole 71 is unmovable, whilethe axial post 31 installed into the active hole 72 is movable withinthe active hole 72. An inner side of each active hole 72 of the seat 14is installed with a pushing unit 80. The pushing unit 80 is furtherinstalled with a transversal rod 81 which is movable inwards andoutwards. An outer end of the transversal rod 81 is connected to anupper end of the axial post 31 within the active hole 72 so as to changethe position of the outer disk 3 (outer belt wheel 33, pulley) foradjusting the tightness of the transfer unit 4 circulating the outerbelt wheel 33). As a result, the transfer unit 4 is capable of drivingeach outer belt wheel 33 effectively.

An upper end of each axial post 31 is formed with a locking means 36which is position above the connecting hole 70. The locking means 36 islocked into a locking hole of the axial post 31 by a longitudinal stud361 so that the seat 14 is clamped between the locking means 36 and theaxial post 31 while the axial post 31 is retained to a respectiveconnecting hole 70. The locking means 36 above the active hole 72 isconnected to an outer end of a respective transversal rod 81.

As illustrated in FIG. 23A, each supporting frame 12 includes aninsertion tube 123 and an outer tube 124. The insertion tube 123 extendsoutwards from the primary body 11. The insertion tube 123 has aninsertion groove 1231 An inner side of the outer tube 124 is insertedinto the insertion groove 1231. An outer side of the outer tube 124 isinserted into a respective one of the grinding knife units 121. An axialsurface of the outer tube 124 is formed as a first plane 1241 and asurfaces of the insertion groove 1231 is formed with a second plane 1232at a position corresponding to the first plane 1241 of the outer tube124. When the outer tube 124 is inserted into the insertion groove 1231,the first plane 1241 is aligned with the second plane so that theinsertion tube 123 does not axially rotate with respect to the outertube 124.

Advantages of the present invention are that installing units arearranged on a seat which is installed with the central disk and theouter rotary disks. In use, it is only needed to buckle the installingunits to the grinding knives on a power source of a cement walk-behindtrowel machine so that the central disk and the outer rotary disks areassembled to the cement walk behind trowel machine. The installing workis easy and convenient. The original grinding knives are unnecessary tobe detached from the cement walk behind trowel machine. Furthermore thegrinding device of the present invention can be detached easily as it isnot used, while the original used grinding knives can be used again. Nomore vehicle is needed. In the present invention, the outer rotary disksare arranged on the periphery of the central disk so as to have a largegrinding area. By the revolution of the outer rotary disks withrespective to the central disk and the rotation of the outer rotarydisks, the cement surface may be ground effectively so that the wholecement surface is uniformly ground to present a beautiful outlook. Thisis beneficial to the succeeding works.

The present invention is thus described, it will be obvious that thesame may be varied in many ways. Such variations are not to be regardedas a departure from the spirit and scope of the present invention, andall such modifications as would be obvious to one skilled in the art areintended to be included within the scope of the following claims.

What is claimed is:
 1. An easy-detachable grinding device for a cementwalk-behind trowel machine which is installed to a power output shaft ofa power source of a cement walk-behind trowel machine, the grindingdevice comprising: a rotation frame including a primary body and aplurality of supporting frames connected to the primary body; a centerof the primary body having a through hole; in assembly, the power outputshaft of the power source being inserted into the through hole so thatthe power source can drive the rotation frame to rotate; each supportingframe extending from the primary body; an outer side of each supportingframe be installed with a grinding knife unit; a seat installed belowthe rotation frame; an upper periphery of the seat being formed with aplurality of installing unit; each installing unit being positionedbelow an outer side of a respective supporting frame; the installingseat serving to be connected to a grinding knife unit; rotation of therotation frame will drive the seat to rotate; a central disk locatedbelow the seat; a center of the central disk having an installing hole;a rotating shaft being installed in the installing hole; the rotatingshaft being fixed therein by using a stepped bearing so that rotation ofthe rotating shaft does not drive the central disk to rotate; therotating shaft extending from the installing hole upwards; an upper endof the rotating shaft connected to the seat; the through hole and therotating shaft being coaxial; when the rotation frame rotates, the seatis driven to rotate so as to drive the rotating shaft to rotate; and aplurality of outer disks arranged below the seat; a center of each outerdisk having an assembly hole; an axial post being installed in theassembly hole; an upper end of each axial post being connected to theseat; a bottom of each outer disk being installed with at least oneouter grinding sheet; and wherein when the power output shaft rotates,the seat is driven to rotate, the power output shaft drives the rotationframe to rotate so that the outer disks revolve around the central disk;as a result, the outer grinding sheets rotate around the central disk soas to grind the surface of the cement ground; and one side of theinstalling unit installed with a trench; in assembly state, one side ofthe grinding knife unit being embedded into the trench so tha theinstalling unit being tightly engaged with the grinding knife unit; onside of the grinding knife unit can be folded upwards so that thegrinding knife unit being extremely steadily fitted to the trench of theinstalling unit.
 2. The easy-detachable grinding device for a cementwalk-behind trowel machine as claimed in claim 1, wherein one side ofthe installing unit is formed with a trench, in assembly state, one sideof the grinding knife unit is embedded into the trench so that theinstalling unit is tightly engaged with the grinding knife unit.
 3. Theeasy-detachable grinding device for a cement walk-behind trowel machineas claimed in claim 2, wherein on side of the grinding knife unit isfolded upwards so that the grinding knife unit is extremely steadilyfitted to the trench of the installing unit.
 4. The easy-detachablegrinding device for a cement walk-behind trowel machine as claimed inclaim 2, wherein all trenches of installing units are arranged at thesame side along a circular path so that all grinding knife units areengaged into the trenches along a clockwise or counterclockwise path. 5.The easy-detachable grinding device for a cement walk-behind trowelmachine as claimed in claim 4, wherein rotation direction of therotation frame is opposite to the direction that the grinding knifeunits engages into the trenches of the installing units, so that as therotation frame rotates, the grinding knife units resist against innerwalls of the trenches for preventing the grinding knife units fromdropping out from the trenches.
 6. The easy-detachable grinding devicefor a cement walk-behind trowel machine as claimed in claim 1, whereinan outer periphery of the central disk is formed with an outer teethunit so that the whole structure is as a central belt wheel; each outerdisk includes disk body and an outer belt wheel fixed to the disk body;the assembly hole is formed in a center of the outer belt wheel; a lowerend of the axial post is fixed to the assembly hole of the outer disk;the outer grinding sheets are installed at a bottom of the disk body;the grinding unit further includes a transfer unit which encircles thecentral belt wheel and the outer belt wheels; when the rotation framerotates, the outer grinding sheets of the outer disks are driven torevolve around the central disk to grind and moreover the transfer unitfurther drives the outer belt wheels to rotate and the outer disksrotate around a center of itself; as a result each outer grinding sheetrevolves around the axial post of the outer disk so as to further grind;then, the central belt wheel rotates or do not rotate with the transferunit.
 7. The grinding device for a cement walk-behind trowel machine asclaimed in claim 1, wherein all the outer rotary disks are spaced withan equal space.
 8. The easy-detachable grinding device for a cementwalk-behind trowel machine as claimed in claim 6, wherein a lower sideof the central belt wheel is arranged with a slide proof pad; aplurality of elastic bodies are arranged between the central belt wheeland the slide proof pad.
 9. The easy-detachable grinding device for acement walk-behind trowel machine as claimed in claim 6, wherein anouter periphery of the seat is formed with a plurality of connectingholes each of which receives an upper end of an axial post of arespective outer disk; the connecting holes are classified as at leastone retaining hole and at least one active hole; the axial postinstalled into the retaining hole is unmovable, while the axial postinstalled into the active hole is movable within the active hole; aninner side of each active hole of the seat is installed with a pushingunit; the pushing unit is further installed with a transversal rod whichis movable inwards and outwards; an outer end of the transversal rod isconnected to an upper end of the axial post within the active hole so asto change the position of the outer disk for adjusting tightness of thetransfer unit circulating the outer belt wheel; as a result, thetransfer unit is capable of driving each outer belt wheel effectively.10. The easy-detachable grinding device for a cement walk-behind trowelmachine as claimed in claim 9, wherein an upper end of each axial postis formed with a locking means which is positioned above the connectinghole; the locking means is locked into a locking hole of the axial postby a longitudinal stud so that the seat is clamped between the lockingmeans and the axial post while the axial post is retained to arespective connecting hole; the locking means above the active hole isconnected to an outer end of a respective transversal rod.
 11. Theeasy-detachable grinding device for a cement walk-behind trowel machineas claimed in claim 1, wherein each supporting frame includes aninsertion tube and an outer tube; the insertion tube extends outwardsfrom the primary body; the insertion tube has an insertion groove; aninner side of the outer tube is inserted into the insertion groove; anouter side of the outer tube is inserted into a respective one of thegrinding knife units.
 13. The easy-detachable grinding device for acement walk-behind trowel machine as claimed in claim 12, wherein anaxial surface of the outer tube is formed as a first plane and asurfaces of the insertion groove is formed with a second plane at aposition corresponding to the first plane of the outer tube; when theouter tube is inserted into the insertion groove, the first plane isaligned with the second plane so that the insertion tube does notaxially rotates with respect to the outer tube.
 14. The easy-detachablegrinding device for a cement walk-behind trowel machine as claimed inclaim 2, wherein the rotating shaft being fixed therein by using astepped bearing to buckle the axial post therein; and a lower end of theaxial post is fixed to the assembly hole of the outer disk by usinganother stepped bearing to buckle the axial post therein.
 15. Theeasy-detachable grinding device for a cement walk-behind trowel machineas claimed in claim 1, wherein the transfer unit is a belt or a chain.16. The easy-detachable grinding device for a cement walk-behind trowelmachine as claimed in claim 1, wherein the seat has a flat sheet form.